Air conditioning system



April 14, 1942.

2 Sheets- Sheet 1 Filed Feb. 6, 1959 ,finomtor m]! 18.19. (BmuwizmmilGHOURQ April 1942- R. B. PNCRAWFORD 2,279,657

AIR CONDITIONING SYSTEM Filed Feb. 6, 1939 2 Sheets-Sheet 2 A mmrmmcmdomI attorney Patented Apr; 14, 1942 UNITE.

stares PATENT OFFICE Ara CONDITIONING SYSTEM Robert B. P.Crawfqrd'Miami, Fla. 3 Application February. 6, m9, Serial Nazsasas14-Claims.. (c1.- sz-e) eration system having an evaporator andcondenser which are selectively connected toa space heat exchange meansto thereby provide for heat- I ing or cooling the space without alteringthe op-' eration of the refrigeration system.

Another object is the provision of a system of this type which utilizesfirst and second space heat exchangers which are alternately connectedto the evaporator and condenser of theTefrigeration system.

A further object is the provision of a system of this general type whichutilizes a storage tank for storing conditioned medium and in which thetemperature of'the stored medium is automatically controlled. Stillanother object is the provision of a timing arrangement for stopping therefrigeration system during peak load periods and for. varying thetemperature of the stored medium prior to such periods to provide forcarrying the system through such periods.

Other objects will appear from the following description and theappended claims. Y

For a full disclosure of this invention, reference is madeto thefollowing detailed description and to the accompanying drawings, inwhich Figure 1 illustrates diagrammatically. an air conditioning systemembodying the principles of this invention, and

Figure 2 is a wiring diagram of the controlsystem of- Figure 1.

' Referring to the drawings, reference character I indicates aconditioning chamber having an in-.

let 2 for freshair. The discharge end of this conditioning chamber isconnected to a fan 3 which in turn is connected by a dischargeduct 4 tothe conditioned space 5. This conditioning chamber contains a first heatexchanger 6 which.

acts as a precooler for the air in summer and as a preheater for the airin winter. Also located in-chamber l is a second heat exchanger 7 whichacts as a cooling coil in summer and as a heating coil in winter. Whilechamber I is illustrated as receiving fresh air only, this chambermay-be arranged to receive .a mixture of fresh air and air recirculatedfrom the space 5, if so desired.

The' cooling and heating system includes a. mechanical refrigerationsystem having a compressor 8 which is driven by an electric motor 9controlled by a three speed starting box it). T e

outlet .of the compressor 8 is connected by a discharge line H to therefrigerant inlet of a condenser !2 which is diagrammaticallyillustrated as comprising a casing housing a cooling coil 53.

The refrigerant outlet of the condenser i2 isconnected by a liquid line[4 to a solenoid valve I5 which is in turn connected by pipe l6 to anevaporator l1; This evaporator i1 is provided with a coil l8. Thetop ofthe evaporator I! is connected'to a suction line l9 having a trap .20

interposed therein for removing any liquid refrigerant which may bewithdrawnfrom the evaporator. The trap is provided witha drip conduit 22which is connected to the inlet pipe "5. The solenoid'valve I5 iscontrolled by means of afloat switch Ml which is responsiveto the levelof the liquid refrigerant in the evaporator l'l. This float switch opensand closes the valve l5in a manner to maintain a constant liquidrefrigerant level inthe evaporator andthus causes theeVapora'tor E1 tobe flooded. As well understoodin the art, the condenser 12 acts toremove heatfi'om the compressed refrigerant. thereby liquefying it, andthis liquid refrigerant evaporates within the evaporator I! for causingthe.

coil It to be chilled. e d

Reference character 25 indicates'a circulating pump which is driven byan electric motor 26. The inletofv this pump is connected to a pipe 21which extends into a well 28. The discharge of pump 25 is connected to apipe 29 which leads to the inlet of the coil 6 located within theconditioning chamber l.' The water flows through this coilin'counterflow relation with the air flow through the conditioningchamber.

' outlet of coil 6 is connected to a pipe 30 which in The turn isconnected to valves 3| and 32, The outlet of valve 3| is connected to apipe 33' leading to the inlet of .coil l8 within the evaporator l1, andthe outlet of this coilis connected by a pipe 34 which is in turnconnected to valves 35'and 36. The outlet'of valve 35 is' connected topipe 31 which leadsinto a sump 38 which is connected to the well 28 by asubterranean ditch 39 located below the prevailing water table. The

valve 32 is connected to a pipe 40 which leads to the inlet of the coil[3 in condenser H. The outlet of this coil is connected by a pipe 4! toa modulating valve 42 which is in-turn connected by pipe 43 to the inletof a three-way valve 65.

One outlet of this three-way valve is connected by pipe 45 to a storagetank 46, this tank inturn being connected. by pipe 41 to the pipe 48which extends between valve 36 and the inlet of a pump Y 49. This pumpis driven by a motor 50 havingv a starter The outlet of this pump isconnected by a pipe 52 to the inlet of coil 1 in conditioning chamber I.The water or other heat exchange medium passes through this coil I incounterfiow relationship to the air being conditioned, and leaves thiscoil through a pipe 53' which is connected by pipes 54 and 55 to -valves56 and 51, respectively. The second outlet of the three-way valve 44 isconnected by a pipe 58 which leads to the sump 38. The pipe 46 whichleads to the inlet of coil I3 in condenser I2 is connected to a citywater service pipe 59, the flow through this pipe being controlled bymeans of a valve 66 which is controlled by a proportioning motor 6|.

The valves 3|, 32, 35, 36, 56, and 51 may be solenoid valves which areadapted to close when deenergized and to open when energized. In amanner which will'be explained hereinafter, the valves 3|, 35, and 51are energized when the system is operating on the winter cycle and thesevalves are marked W. The valves 32, 36, and 56 are deenergized duringthe winter cycle and are energized during the summer cycle and areaccordingly marked S.

Thus during the winter cycle, the W valves are open while the S valvesare closed With the valves in these positions, the pump 25 will act towithdraw water from'the well 28, which water will be higher than thetemperature of the incoming air. This water will be discharged throughthe pipe 29 into coil 6 through which it flows in counterflowrelationship with the air thereby preheating the air. This water willthen flow through the pipe 36, valve 3|, and pipe 33 into coil l8 of theevaporator l1, and thereby provides a source of heat for thisevaporator. This water will-then flow through pipe 34, valve 35, andpipe 31 into sump 38 from which'it may flow through the subterraneanditch 39 back to the well 28. The water in flowing through this ditchlocated below the water table will absorb storage tank 46 if the valve44 is positioned to permit this.

Also at this time, the pump 49 will withdraw cold water from the coil'l8 of evaporator l1 through pipe 34, valve 36 and pipe 46. This coldwater will pass through the pipe 52 into the coil 1 for thereby coolingthe air being passed to the space. The water leaving this coil will flowthrough pipe 53, pipe 54, valve 56, and pipe 33 to the inlet of coil |8in the evaporator l1.

From the description thus far, it will be apparent that during both theheating cycle and the cooling cycle the pump 25 will act to withdrawwater from the well 28 and pass it through the coil 6 in theconditioning chamber l. During the heating cycle this will act topreheat the air and during the cooling cycle this will act to pre-;

1 is passed directly back to the inlet of coil I8. I

When the system is operating on the heating cycle however, the waterleaving the coil 6 which then acts as a preheater will pass directlyinto coil l8 of evaporator [1 for thereby-providing a. source of heatand the cold water leaving coil l8 will pass to the sump 38. At time,hot water is withdrawn from the storage tank 46 and passed through thecoil 1 in conditioning chamber I. This water then passes through valve51 into the inlet of coil l3 in which it is heated, the

heat from the surrounding sub-strata and water.

At the same time, water will be withdrawn from the storage tank 46through pipes 41 and 48 by the pump 49, this pump discharging this waterthrough the pipe 52 and into the coil 1. The

water will flow from the coil 1' through pipes tank 46. This storagetank may have a take-oil 46a' for domestic hot water.

During the cooling cycle the W valves 3|, 35, and 31 will beclosed whilethe S valves 32, 36, and 56 willbe open. At this time, the well waterwill be cooler than the 'air passing over coil 6 and consequently thepump 25 in forcing water from the well 28 through coil 6 causes the airto be precooled. The water flowing from the coil 6 passes through pipe36, valve 32, and pipe 46 intothe coil l3 of condenser l2 for condensingthe compressed refrigerant. The heated water flowing from .coil |3passes through pipe 4|, valve 42, and pipe 43 to the three-way valve 44.This water will then flow through the pipe 58 back to the sump 38 if thevalve is in the position illustrated, or will flow through the pipe.into the The water in flowing through i ire.

hot water passing through the valves 42 and 32, valve 43 back intostorage tank 46. Thus in summer the coil 1 receives cold water from theevaporator I1 and .in winter this coil receives hot water from thecondenser l2.

Referring now to the controls for the system. reference-characterindicates a thermostat responsive to outdoor temperature, thisthermostat controlling a motor 66 operating a step controller 61. Thisstep 'controller 61 is connected to the W and S valves and acts to openthe S valves 32, 36, and 56 when outdoor temperature rises above 15 F.and to, open the W valves 3|, 35, and 51 when outdoor temperature fallsbelow 60 F. This step controller 61 also is connected to the pump motorstarter 5| for stopping trolled by the step controller 61. This relay 16acts to place the step control motor 69 under the control of a summerspacethermostat 11 when theoutside temperature is above F., whileplacing this step control motor 69 under the con-.

trol of a winter space thermostat 12 and a. low limit dischargethermostat 13 when outside temperature is below this value. The stepcontroller 61 also operates through a relay -14 in the compressorstarter for preventing operation of the compressor when outsidetemperature is between .60 F. and 75 F.- The three-way valve 44 and thecity water valve 66 are selectively controlled by means of a pressurecontroller 15 on the hot water tank 46 through a relay I6 which iscontrolled by the step controller 61. 'This relay acts to place thecontroller I in control of the valve 6| when the system is operating onthe heating cycle while placing the controller in controlof thethree-way valve 44 when the system operates on the cooling cycle. valve82 is controlled by a thermostat TI which is responsive to thetemperature of the water in tank 46 and also by a timer I8 whichfunctions to vary the setting of controller IT in .a manner to increasethe temperature of the water in tank a 46 to a predetermined valuebefore a peak load period for the power service approaches.

the compressor during such peak load periods.

The throttlin This timer 18 also functions to prevent operation ofReferring now to Figure 2, the details of the 1 control system 'will bedescribed. The outside thermostat 65 is preferably of the potentiometertype and is diagrammatically illustrated as comprising a bellows 89connected by tube 8| to a bulb 82 located in the fresh air inlet. Thisbellows actuates a bell-crank lever having an actuating arm 83 connectedto a spring 84 and a slider' 85 which cooperates with a controlresistance 86 to form a control potentiometer. It will be apparentthatupon rise in temperature of the fresh air the bellows .89 willexpand thus causing movement of slider 85 to the right along resistance86 against the action of spring 84, and that upon fall in temperaturethe bellows 99 will contract under the action of'spring 84 "for causingmovement of' the slider in the opposite direction. This instrument maybeso designed and adjusted as to cause slider 85 to engage the righthandend of resistance 86 when outdoor temperature is at or above 75 F.,while engaging the lefthand end of this resistance when outdoortemperature is at or below 69 F.

The motor 66 which actuatesthe step controller 61 is preferably of thetype shown in the Taylor Patent No. 2,028,110. This motor is connectedto the thermostat 65 and is adapted to assume angular positionscorresponding to the position of the slider 85 on resistance 86. Thismotor 66 is provided with a shaft 81 which carries the step controllercams 88, 99, and 99. These cams cooperate with suitable followers foractuating mercury switches 9|, 92, and 93, respectively. When outsidetemperature is at or above 75 F., the shaft 9! of motor 66 assumes theextreme clockwise position shown at which the raised portions of earns98 and 99 just engage the cam followers for tilting mercury switches 9|and 93 so as to bridge the left-hand electrodes of switch 9|, and theelectrodes of switch 93. At this time, the raised portion of the and 51.

mercury switch 9| will be closed. When outside temperature is between 75and 60 F., the mercury switches 92 and 93 will both be open and mercuryswitch 9| will be tilted for bridging its right-hand electrodes. Whenoutside temperature is below 60 F., the mercury switch 92 will close andthe right-hand electrodes of switch 9| will remain bridged.

The mercury switches 9| and 92 control the S valves 32, 36, and 56 andthe W valves 3|, 35, When the outside temperature is at or above 75 F.,the switch 93 is closed and the switch 92 is open as described above.Due to switch 93 being closed, a circuit will be com-' V the mercuryswitch 92 is open and the W valves 3|, 35, and 51 are deenergized andconsequently are closed. -When outside temperature falls below 75 F.,but is above 60 F., both the S valves and W valves will be deenergized,due to mercury switches 92 and 93 being open. Upon fall in outsidetemperature below 60 F., the mercury switch 92 will close which willcomplete "a circuit from the transformer secondary 94, wires 96, IN, andI92, mercury switch 92, and wire I93 cam 89engages the cam follower formercury switch 92 and tilts this switch to open position. Upon fall .inoutside temperature, the slider 85 of thermostat will begin to move tothe left on resistance 96 which causes proportionate rotation of shaft81 in a counter-clockwise 'direction. This immediately causes the raisedportions of cams 88 and 99 to disengage their respective cam followersthereby tilting mercury switch 9| for bridging'its right-hand electrodesand tilting. mercury switch; 93 to'open position. When outsidetemperature falls to 60 F., the shaft 81 will have rotated sufficientlyto cause the raised portion of cam 89 to disengage itsfolr lower forthereby tilting mercury switch 92 to through Wvalves 3|,35, and 5'! inparallel to wire I99 and wires I95, 99 and I99 to secondary 99.Therefore when outside temperature is above'75 F., the S valves 32, 36,and 56 are open and the W valves 3|, 35, andSI are closed. When outsidetemperature is between '75 F. and 60 F., all of the valves will beclosed, and when the 3|,35, and 51 will open.

Referring now to" the compressor speed con trols, the compressor motor 9is of the threespeed type and is provided with the three-speed startingbox I9. This three-speed starting box is provided with a common terminalconnected to wire I91, a low speed terminal connected to wire I98, anintermediate speed terminal connected to wire- I99, and a high speedterminal connected to wire II9. The wires I98, I99, and III) leaddirectly to the step controller 68 and the wire I9'I leads to the relay19.

.The relay I9 may be of any desired type .and is diagrammaticallyillustrated as including a pull-in coil III which actuates a switch arm-I I2 through a suitable armature II3. .When coil III is energized, theswitch arm H2 is caused to engage contact I'M, whilewhen coil III isdeenergized the switch arm II2 disengages contact II4 due tothe actionof gravity of springs; not

The step controller 68 includes cams II5,'II6, and II! which' aremounted upon the shaft II8 of motor 69 and which through suitablefollowers actuate mercury switches II9, I29, and I2I., The cams H5, H6,and III are attached .to the shaft 8 in staggered relationship so thatupon clock wise rotation ofshaft II8, the mercuryswitches closedposition. It will therefore be seen that when outside temperature is ator above F the mercury switch'92 will be open,, the mercury orderstated. .When the shaft III; of motor 69 is in its extremecounterclockwise position, the

- mercury switches I I9, I29 andIZI will all beopen and consequently thecompressor motor 9 will not operate. As shaft II8 rotates in a clockwisedirection, mercury switch II9 will first close. As-

suming that relay 14 is energized, a circuit will be completed from thecommon terminal of starter I through wire I01, relay 14, wires I22 andI23, mercur switch I I9, and wire I08 to the low speed terminal of thestarter I0 thereby causing the compressor to operate at low speed. Uponfurther rotation of shaft II8, thevmercury switch I20 will close forthereby completing a circuit from the common terminal through thisswitch and wire I09 to the intermediate-speed terminal for causingoperation of the compressor at intermediate speed. Upon still furtherrotation of shaft II8, the mercury switch I2I will close for Icompleting a circuit through wire IIO to the high speed terminal therebycausing the compressor to operate at high speed. From the foregoing, itwill be-apparent that the compressor speed will vary in accordance withthe angular position of the shaft II8 when the relay 14 is energized, Itwill also be apparent that when relay 14 is deenergized, the compressorwill not operate regardless of the position of shaft H8.

The motor 69 is preferably of the type-shown in the Taylor Patent No.2,028,110 and is controlled by the relay 10, the summer thermostat H,the winter thermostat 12, and the discharge thermostat 13. Thesummerthermostat may be of the potentiometer type and includes a bellows I25which actuates a bell-crank having an actuating arm I26 biased by aspring I21, and a control arm or slider, I28 which cooperates with a ergized, the switch arms engage the out contacts.

As mentioned before, the motor 69 is preferably of the type shown in theTaylor Patent 2,028,110. This motor includes three control terminalswhich are marked R, W, and B, and is adapted to assume intermediatepositions depending upon the relative values of resistances connectedbetween'terminals R and W and between terminals R and B. When equalresistances are connected between terminals R and W and betweenterminals R and B, this motor will assume mid position as shown whichcauses closing of mercury switches H9 and I for operating th compressormotor 9 at intermediate speed. If the resistance between terminals RandW is decreased without corresponding decrease resistance I29 to form acontrol potentiometer. 1

Upon an increas in space temperature, the bellows I25 will expandagainst the action of spring I21 for shifting the slider I28 to the leftalong resistance I29, while upon decrease in temperature the bellows I25will contract under the action of spring I21 for shifting slider I28 inthe opposite direction. This instrument may be so designed and adjustedas to cause the slider I28 to engage the right-hand end of resistanceI29 when space tempera-ture is at or below"15 F..

while engaging the left-hand end of this resistance when spacetemperature is at or above 80 The winter space thermostat 12 may beexactly the same as the summer thermostat H and includes a slider I30and a resistance I3I. This instrument may be designed and adjusted in amanner to cause the slider I30 to engage the lefthand end of resistanceI3I when the space temperature is at or above 72 F., while engaging theright-hand end of this resistance when the space temperature. is at orbelow 70 F. I

The discharge thermostat 13 may be similar to the spacethermostats-H and12 and includes a bellows I32, a slider I33, and a resistance I34.'

actuates through a suitable armature the switch arms I38, I39, and Iwhich cooperate with in contacts I4I, I42, and I43, respectively, andalso which cooperate with out contacts I44, I45, and 46, respectively.When coil I31 is energized, the switch arms I38, I39, and I40 engagerthe in contacts, while when coil I31 is deen in resistance betweenterminals R and B, the motor 69 will operate in a counter-clockwisedirec-' tion for decreasing the-compressor speed, and conversely, if theresistance between terminals R and B is decreased without correspondingdecrease in resistance between terminals R and W,

the motor 69 will operate in the clockwise direction for increasing thecompressor speed,

The pull-in coil I31 of the relay I0 is controlled by the mercury'switch9I of the step controller 61. When outside temperature is at or aboveF., this mercury switch will be tilted as shown for bridging itsleft-hand electrodes and this will energize pull-in coil I31 as follows:transformer secondary 94, wires 95, II and I50, left-hand electrodes ofswitch.9 I wire I5I', pull-in coil I31, and wires I52, I05, 99 and I00to transformer secondary 94.

It will thus be apparent that when outside temperature is at or above 75F., the coil I31 will be energized for causing the switch arms I38, I39and I40 to engage their in contacts. However, when outside temperatureis below 75 F., these switch arms will engage their out contacts.

Assuming that outside temperature is above 7 5 F., thereby energizingthe relay I0, the switch arms I38, I 39,and I40 will engage the incontacts, as shown. Engagement of switch arm I39 with contact I42 willconnect terminal R of the motor 69 to the slider I28 of the summerthermostat 1I through wire I53, switch arm I39, contact I42, and wire'I54. Engagement of switch arm I38 with contact I4I will connect terminalW of motor 69 to the right-hand end of resistance 429 through wires I55and I56, while engagement of switch arm I40 with contact I43 willconnect terminal B to the left-hand end of resistance I29 through wiresI51 and I58. Consequently, the summer thermostat H is placed intocontrol of the motor 69 which controls the compressor speed, With thespace temperature at an intermediate value, the slider I28 engages the.center of resistance I29 which divides the resistance I29 equallybetween terminals R and W and terminals Rand B. This causes the motor 69to assume the position shown at which mercury'switches H9 and I20 areclosed for operating the compressor at intermediate speed. Upon rise inspace temperature, the slider I29 will shift to the left alongresistance I29 thereby decreasing the portion of this resistance whichis between terminals R and B, while increasing the portion betweenterminals R and W. This will cause the motor 69 to rotateproportionately in the clockwise direction thereby causing closing ofthe switch I2I for operating the compressor at high speed. Upon'decfeasein space temperature from this intermediate value. the slider I20 willshift to the right along resistance I29 thereby decreasing the.proportion of this resistance which is between terminals R and W, whichwill cause the motor 63 to operate in the counterclockwise directionthus tilting mercury switch I20 to open position which will cause thecompressor to operate at low speed. Upon continued decrease in spacetemperature, the motor 69 will rotate further in the counterclockwisedirection thus causing opening of switch 123 to stop the compressor whenthe space temperature falls to 75 F. Therefore, when outside temperatureis at or above 75 F., the summer thermostat H is placed in control ofthe compressor, acting to place the compressor into operation at lowspeed when space temperature rises above 75 F. and to graduatinglyincrease the compressor speed upon increase in space temperature forcausing the compressor to operate at maximum speed when the spacetemperature rises to 80 F.

When outside temperature falls below 75 F., the mercury switch 3| ofstep controller 61 will be tilted so as to unbridge its left-handelectrodes and bridge its righthand electrodes. This unbridging of theleft-hand electrodes will break the energizing circuit or the relay 10thereby causing the switch arms I38, I39 and I40 to engage their outcontacts. This will completely shifts to the right along resistance I34,it acts 69 for causing this motor to increase the compressor speed. Thusas the discharge temperature falls below the setting of the dischargethermostat 13, this thermostat actsto increase the compressor speedindependently of the thermostat 12 for thereby preventing thedischarge-temperature from falling too low. It will be noted thatresistance I68 is connected to the wires I5I and I65 and is thusconnected across terminals R and B of motor 89. The purpose of thisresistance is to balance out the effect of the resistance I34 ofcontroller 13 which is connected between terminals R and W of motor 69when this thermo-= stat is in satisfied or normal position. -Thisresistance I68'should be equalin value to the resistance I34.

From the description thus far, it will be seen that when the outsidetemperature is above 75 F., the summer thermostat H is placed in controlof the compressor speed controller and acts in a manner to increase thecompressor speed as space temperature increases. When outsidetemperature falls below 75 F., the step controller .61 deenergizes therelay 10 which disdisconnect the summer thermostat from the.

motor 69. Engagement of'the switch arm I39 with contact motor 69 to theslider I33 of the discharge thermostat 13 by wires I53, I60 and I6I. Ifthe slider I33 is engaging the left-hand end of resistance I34 as occurswhen the discharge temperature is sufficiently high, this circuit fromterminal R of the motor will be carried through wire I62 to the slider Iof the winter thermostat 12. Due to the switch arm I38 engaging contactI44, terminal W of motor 69 will be connected to the left-hand end ofresistance I3I by wires I55 and I63.- Also due tothe switch arm I40engaging I will connect terminal R ofconnects the summer thermostat Hfrom the compressor speed controller and places the win- I ter spacethermostat 12 and the discharge controller 13 in control of thecompressor speed controller. At this time, the controller 12 acts toincrease the compressor speed upon fall in space temperature and thedischarge thermostat 13 acts to prevent the discharge temperature fromfalling below the desired value.

contact I46, terminal B of motor 69. will now be connected by wires I51,I64, and I65 to the righthand end of resistance I3I. Therefore when therelay 10 is deenergized' and the discharge temperature is at or above 65F., the thermostat 12 will be in control of the step controller motor69. If the space temperature is above 72 F., terminals R and W of themotor will besubstantially shortcircuited for thereby rotating the shaftI I8 of the step. controller in a direction for stoppingthe compressor.As the space temperature decreases below 72 R, the slider I30 will beginmoving to the right across resistance I3I thereby inserting 'aportion ofthis resistance between terminals R and W and removing. this resistancefrom between terminals R andB. This will cause the'motor shaft I I8 torotate proportionatelyin a clockwise direction thus starting thecompressor and increasing its speed as the space temperature falls.

,It will. be noted thatthe right-hand end'of connected by Wires 161,166,I-65,.I 64,.contact; I46,

stat 12 thereby decreasing the efiect of this thermostat upon the motor.Also as the slider I33 Referring now to the controls for tank- 46, itwill be noted that this tank is closed at its top to provide an airspace abovethe water level. The water level with this tank is controlledfor maintaining a substantially constant pressure within the tank, thepressure controller 15 being selectively connected to the valve 60 orthe valve 44 through the relay 16. The pressure controller 15 mayconsist of a bellows I10 which is connected to the tank 46 by .atubeI1I. This bellows actuates a bell-crank lever having an actuating armI12 and a slider I13 cooperating with a resistance I14. Upon increase inpressure within tank 46, the bellows I10 will expand against the actionof spring I15 for causing the slider I13 to shift to the leftacrossresistance I14. This instrumentmay be adjusted in a manner tocause the slider I13. to. engage the lefthand end of resistance I14 when,the tank pressure is at 40 poundspe'r square inch and to engage theright-hand end-{of ..resistance. I13

when th essure is ago? below mpdunldszper .Sq-uareinch n The relay 15include '4 a coil I 16, which actuates switcl arms I11, I18, I19, I80,aii d'I8I. The switch arms I11, I18, ,I19,Ia nd I80. cooperatewith.foutiflpontactS, I02, 83,184, and I85Eand switcharms- I18, 'I19, l8f0,.andl I8 I cooperate with in contacts I86, I81, I88, and I 8j 9'.".When the c unt i 'deenergized, t e switch arms l 11, [l8,,I19 and I80engage their out contacts and when' the coil .I 1I5is energized, theswitch arms I18, I19, I80, and 1,8 l ,.engage their respective incontacts. The coil I16 is .controlle d'by the merci ry swi tch" of theoutdoor temperature .step controller.61'.'. Wheri outdoor temperaturefalls, below F.. the mercury switch 9I istilted for bridging itsrightliand electrodes. "I'lfiswill energize coil I16 as follows:transformer secinto tank 46.

ondary 94, wires 98, IOI and I50, right-hand elec- V trodes of switch9|, wire I90, coil I18, wires I9I,

I92, and I to secondary 94. Therefore'when outdoor temperature is below75 F., the coil I16 is energized for causing the various switch arms to'engage their in contacts. When outdoor temperature is above 75 F., thecoil I18 is de-- energized for causing the switch arms to engage theirout contacts, as shown.

The three-way valve 44 is positioned by means of a proportioning motorI95 having terminals R, W, and B. When the relay 18 is deenergized dueto outside temperature being above 75 F., the slider I13 of the pressurecontroller is connected to terminal R of motor I95 by wire- I98, switcharm I19, contact I84, and wire I91. Also, the right-hand end ofresistance I14 is connected to terminal B by wire I98, switch arm I80,contact I85, and wire I99. At this time,

the left-hand end of resistance I13 is connected by wire 200, switch armI18, contact I83, and

flowing through pipe 43 to be divided between the storage tank 48 andthewaste pipe 58. If the pressure within tank 48 falls due towithdrawing of water from this tank for domestic use, the slider I13will shift ,to the left across resistance I14 thus decreasing theportion of this resistance between terminals .R and B for causing themotor I95 to position valve 44 in a manher to increase the flow of waterinto tank 48.

Conversely, upon increase in pressure with the tank 46, the slider I13will shift to the left across resistance I14 thereby causing the motorI95 to position valve 44 for decreasing the flow of water When thepressure within this tank rises to pounds vper square. inch, the valve44 will be positioned for preventing further flow of water into thistank.

When outside temperature falls below"15 F., the mercury switch 9| willenergize the relay I18 for causing the various switch arms to disengagetheir out" contacts and to engage their in contacts. This willcompletely disconnect the pressure controller 15 from the three-wayvalve motor I95. Due to the switch arm I8I of relay 18 engaging contact489, terminals R and Bof motor I95 will be short-circuited through wiresI91, 202, switch arm I8I, contact I89, and

wire I99. This causes the motor I95 to position the valve 44 for causingall of the water flowing in pipe 43 to flow into tank 48.

I Due to-the relay 18 now being'energized, the slider I18 of pressurecontroller 15 will be conpipe 43, valve 44, and pipe 45 into tank at.When the pressure in the tank is above 40 pounds per square inch, thecontroller 15 will cause the valve to be closed, while upon fall inpressure below this value the valve 80 will be graduatingly opened.

When outside temperature is above 15 F., thus causing the relay 18 to bedeenergized, the switch arm I11 engages the contact I82 which connectsterminals R and W of motor 6| through wires 203, 208, switch arm I11,contact I82, and wire 205. From the foregoing, it will be seen that whenoutside temperature is above F., the pressure controller 15 is placed incontrol of the three-way valve 44' and the valve.80 is driven to closedposition. 'However, when outside temperature falls below this value, thepressure controller 15 is placed in control of the valve and thethree-way. valve 44 is driven to a position for causing all of the waterflowing through pipe 43 to flow into the tank 48.

The throttling valve 42 is provided for the purpose of restrictingthe'flow of water through the coil I3 in condenser I2 for, therebyinsuring that the water is heated to the desired point during its fiowthrough this coil. This valve is positioned bya proportioning motor 208which is controlled by the thermostat 11 responsive to the temperatureof the water in tank 48. The thermostat 11 may comprise a bellows 209which actuates a lever arm 2I0 against the action of spring 2. Theleverarm 2I0 actuates a slider 2I2 which cooperates with a resistance 2I3 toform a control potentiometer for the motor 208. This lever 2I0 alsoactuates a corrector arm 2I4 which cooperates with a center tappedresistance 2I5. The bellows 209 is connected by a capillary tube 2I8 toa,bulb 2E1 located in the tank 46 (Figure 1).

The right-hand end of the resistance 2I3 is connected by wires 2I8 and2I8a to terminal B of motor 208 and the lefthand end of this resistanceis connected by wires 2I9 and 220 to terminal W of this motor. rectorarm 2I4 of thermostat .11 are electrically connected and the resistance2 I5 is connected by wires 22I and 222 to terminal R of motor 208. Thusthe slider 2I2 is connected to terminal R through the corrector arm 2I4and corrector resistance 2I5. The thermostat 11 is of the wide rangetype and causes motor 208 to shift valve 42 from wide open position to aminimum flow position upon movement of the slider 2I2 over but a smallportion of the resistance 2I3. This controller may be arranged so thatthe slider 2I2 engages the right-hand end of resistance 2I3 'when thewater temperature rises to 160 F.

while engaging the left-hand end ofthis resistance when the watertemperature falls to F. Upon a slight movement of the slider 2I2 to theright across resistance 2 I3, the resistance between terminals R and Bwill be decreased for nected to terminal R of motor. 8| which operatesthe valve 80 by wire I98, switch arm I19, contact I81, and wire 208. Theright-hand end'of resistance I14 will be connected to terminal B ofmotor H by wire I98, switch arm I80, contact I88, and wire 204, whilethe left-hand end of resistance I14 will be connected to terminal W ormotor 8| by wire 200, switch arm I18, contact I88 and wire 205..Therefore the pressure controller 15 at this time is placed under thecontrol of the valve 80 which controls the flow of city water throughpipe 59 into the coil I3 of con- ,denser I2, and thus through pipe 4|,valve 42,

causing valve 42 to open'thereby increasing the flow of water throughcoil 43 for allowing the watertemperature to fall. Conversely, upon aslight decrease in temperature, the slider 2I2 will be shifted slightlyto the left across resistance. 2I3 thus decreasing the resistancebetween terminals R and W of motor 208 for positioning the .valve 42 ina manner to restrict the flow of water.

pletely even when the motor reaches the end The slider 2I2 and cor-' ofits travel. This prevents the flow of water through the condenser frombeing completely stopped by Valve 42.

It is a feature of this invention to prevent operation of the compressorduring peak load periods for the power service and to provide forincreasing the temperature in tank 46 at a predetermined time befoze thepeak load period in order to-provide an adequate supply of hot water tolast through the period when the compressor is stopped. This result isobtained by the timer l8 and a pair of compensating or adjustingpotentiometers 225 and 226. The timer 18 may consist of a suitablysynchronous motor and gear train mechanism 221 having a shaft 228 whichis rotated one revolution every twenty-four hours. This shaft 228carries cams 229 and 230 which actuate mercury switches 23l and 232.-For purposes of illustration, it is assumed that only one peak loadperiod occurs each day, and the cams 229 and 238 are provided withsingle raised por-' tions corresponding to the peak load period. It willbe noted that upon clockwise rotation of the shaft 228, the raisedportion of the cam 229 will engage its cam follower a predetermined timein advance of the time when the raised portion of the cam 23D engagesits cam follower.

The mercury switch 232 controls the compressor relay M, the energizingcircuit for the relay 14 also being controlled by the mercury switches92 and 93 of the outdoor step controller 61. When outdoor temperature isabove 75 F., the compressor relay 14 will be energized through mercuryswitches 93 and 232 as follows: transformer secondary 96, wire 96, wire91, mercury 1 switch 93, wire 233, wire 234, mercury switch 232, wire235, relay coil II I, and wires 99 and N16 to secondary 95. When outsidetemperature falls below 75 the mercury switch 93 will be opened whichwill break the circuit just traced for preventing operation of thecompressor. When outside temperature falls to 60 F. for causing closingof'mercury switch 93, the energizing circuit for relay M will beestablished through this mercury switch as follows: secondary 96, wires96, NH and I02, mercury switch 92, wire 236, wire 234, mercury switch232, wire 235, relay coil Ill, and wires 99 and Hill to secondary 94. Itwill therefore be seen that the mercury switch 232 of the timer 18 isalways in circuit with the compressor relay l4 and that when thismercury switch is open, the relay M is deenergized for preventingoperation of the.

compressor.

'The mercury switch 231 has its common electrodes connected by wires 23!and 222 to terminal R of motor 208. The right-handelectrode of. thisswitch is connected by wire 238 to the slider 239 of potentiometer 226,and the left-hand electrode of this switch is connected by wire 240 tothe slider 24! of potentiometer 225. The resistances 242 and 243 ofthese potentiometers are connected across terminals W and B of-motor208, as shown. It will therefore be seen that the mercury switch 23lacts to place either the potentiometer 225 or the potentiometer 226across the motor control terminals in parallel with the thermostat ll.Each of these potentiometers acts to determine the temperature of thewater which will be maintained by the thermostat 11. For instance, ifthe slider 239 of potentiometer 226 is shifted to the right across itsresistance 2 43, it will decrease the amount of resistance betweenterminals R and B and increase the amount of resistance betweenterminals R and W. This will cause the valve 42 to be opened further'mercury switch 23| of timer [8 'will'place the potentiometer 226 intothe control circuit of motor 208 for thereby causing the tank thermostatH to maintain a relatively low water temperature such as 125 F. As thepeak load period for the power service approaches, the cam 229 will'tiltmercury switch 22 to its opposite position for removing potentiometer226 from the motor control circuit and substituting the potentiometer225. This will raise the water temperature maintained by the tankthermostat Thereafter, the cam 230 will cause opening of mercury-switch232 for stopping the compressor during the peak load period. It will beapparent from the foregoing that during normal operation of the system,the tank thermostat 11 operates to maintain a relatively low tanktemperature for thus'permitting the refrigeration system to operate atalow head pressure securing maximum operating efficiency. Then as thepeak load period for the power service approaches, the

, timer I8 substitutes the potentiometer 225 into the control circuit inplace of potentiometer 226 for thereby raising the tank temperature soas to store sufiicient heat for carrying the system '94 by wires I00,I92 and 254.

over the peak load period when the compressor is stopped.

Referring to the pump controller 5|, this controller may consist of apull-in coil 250 'for operating a switch arm 25I engaging a contact 252.The pull-in coil 250 is connected to the mercury switches 92 and 93 bymeans of wire 253 and wires 233 and 236. The left-hand end of coil 250is also connected to the transformer secondary It will therefore beapparent that whenever the mercury switch 92 or 93 are positioned forpermitting operation of the compressor, the pump starter 5| will beenergized for placing the pump 50 into operation Operation With theparts in the position shown, the outdoor temperature is above F. asindicated by the slider of the step controller 65 engaging theright-hand end of resistance 86. This has caused the step controllermotor 66 to assume its clockwise limit of rotation at which the mercuryswitch 91 is positioned for bridging its left' hand electrodes, themercury switch 92 is open, and the mercury switch 93 is closed. Due tothe mercury switch 92 being open, the W valves 3i, 35, and 51 are closedwhile due to switch 93 being closed the S valves 32, 36, and 56 areopen. This closure of mercury switch 93 also has caused energization ofthe pump motor starter 5| for placing'the pump in operation and also hasenergized the compressor relay T4 through switch 232 of the timer 78 forplacing the compressor under the control of the step controller 68.

Due to the S valves being openand the W valves being closed, cold waterwill be withdrawn With the sliders 239 and 24,l.in-the positions fromthe coil I8 of evaporator l1 through pipe 34 passing through valve 36and pipe 48 to the inlet of pump 49 from which it passes through pipe 52to the 'coil 1 which acts as a cooling coil.

acts to precool the incoming air. The water.

leaving coil 6 then flows through pipe 39, valve 32, and pipe 49 tothecondenser coil I3 for thereby cooling the refrigerant compressed by thecompressor. The water'in passing through the condenser becomes heatedand flows through valve 42 to the valve 44 which divides this streambetween the storage tank 46 and the waste pipe I95 to position the valve44 for passing all of the water flowing through pipe 43 into the tank46. Deenergization of the relay 16 will cause the summer thermostat tobe disconnected from the step controller motor 69 and to place thismotor under the -control of the winter space thermostat 12 and thedischarge thermostat 13. However, due to the opening of switch 93 orstepcontroller 61 at this time, the relays 5I and 14 will be deenergizedand the compressor 8 and the circulating pump 49 will not be inoperation. With outside temperature at this value, no conditioning isnecessary for the space and until outside temperature falls toapproximately 60 F., no heating will be necessary.

When outside temperature falls to 60 F., the mercury switch 92 willclose which will energize the pump starter 5| for placing the pump 49into 58. At this time, it will be noted that the relay 16 is deenergizedwhich acts to place the pressure controller 15 in control of the motor.I95 which positions the three-way valve 44. Thus when the pressurewithin tank 46 is at the predetermined value, such as 40* pounds persquare inch, the valve 44 assumes the position shown which causes all ofthe water leaving condenser coil I3 to pass through the waste pipe 58 tothe sump38 from which it flows through the subterranean ditch 39 back tothe well 28. As the pressure within tank 46 lowers, the motor I95 willposition valve 44 for permitting flow of a portion of the water intotank 46.

With the mercury switch 3| in the position shown, the relay 10 isenergized which acts to place the compressor stencontroller under thecontrol of the summer thermostat 1|. This thermostat acts to increasethe compressor speed as the space temperature increases to thereby varythe refrigeration in accordance with the cooling load upon the system.

The thermostat 11 which is responsive to the temperature of the water intank 46 will control the-valve 42 in a manner to close valve 42progressively with decrease in temperaturewithin tank 46; Thisrestriction of the water flow causes the water to be heatedto a highertemperature as it flows through the condenser I2 and thus provides formaintaining the water in tank 46 at the desired temperature. With thetimer in the position shown, the low temperature potentiometer 226 isconnected into the control circuit of motor 208 which causes thethermostat 11 to maintain the tank temperature at the desired normalvalue. As the peak load period for the power service approaches, the cam229 will tilt mercury switch 23 I to its opposite position foroperationand will also energize the compressor relay 14 for permittingoperation of the compressor under the control of the winter spacethermostat 12 and the discharge thermostat 13. These thermostats willthen operate to control the speed of the compressor in a manner toprevent the space temperature from falling below the setting ofthermostat 12 and to prevent the discharge temperature from falling'below the setting of discharge thermostat 13.

At this time, the S valves 32, 36, and 56 will be deenergized and the Wvalves 3|, 35, and 51 will be energized through the mercury switch 92.Due to. valves 3i, 35, and 51 being opened, water will flow from thecoil 1 through pipes 53 and 55 to valve 51, then through pipe 46 to coilI3 of condenser I2 wherein it is heated. This now placing the hightemperature potentiometer 225 into the motor control circuit therebycausing the tank water temperature to be increased for thereby storingup additional heat. When the peak load period occurs, the mercury switch232 of the timer 18 will be opened which acts to deenergize thecompressor relay 14 thereby placing the compressor out of operation.

When outside temperature falls below 75 F the mercury switch 9| of thestep controller 61 will tilt to its opposite position which acts toenergize the relay I6 and to dleenergize the relay 10. Energization ofthe relay 16 will disconnect the pressure controller 15 from thethree-way valve motor I95 and connect this pressure controller to thecity water supplyvalve motor 6|. Energization of this relay will alsocause motor heated water will then flow through the throttling valve 42to the three-way valve 44 which will now be positioned for passing allof this water to tank 46. Water will then flow from this tank throughthe circulating pipe 41 and pipe 46 to the pump 49 which discharges thishot Water through the pipe 52 to the coil 1. Also, the pump 25 willwithdraw water from well 28 passing it through the coil 6 which acts asa preheater, this water then passing through pipe 30, valve 3|, and pipe33 to coil I8 in the evaporator I1 and through pipe 34, valve 35, andpipe 31 to the sump 38. Therefore when the system is operating on theheating cycle, the coil 1 receives hot water from the storage tank 46which in turn is heated by the condenser I2. Also, the well water afterpreheating the air passes through the evaporator I1 for thus providing asource of heat for the refrigeration system.

During the heating cycle, the thermostat 11 will control the throttlingvalve 42 just as it does during the cooling cycle. Also, the timer 18will act to stop the compressor during peak load periods and to raisethe water temperature in,

tank 46 prior to these peak load periods for thereby storing up heat foruse during the, peak load It should be noted that the timer 18 stopsonly the compressor and permits the circulating pump 50 to continue tooperate for thereby supplying heat to the space even when the compressoris not operating.

From the foregoing description, it will be apparent that this inventionhas provided a system for heating andcooling a space by means of arefrigeration system, the system being caused to selectively heat orcool by changing the water piping connections, thereby permitting therefrigeration system to operate in the same manner at all times. It willalso be apparent that this invention provid% an automatically conditionsboth in summer and in winter and for also maintaining a supply ofdomestic hot water..

While throughout this description definite values of temperature andpressure have been mentioned for illustrative purposes, it will beapparent that these values may be varied as desired for differentinstallations and applications of this invention. Also, while I haveshown but one embodiment of this invention, the invention is not limitedto the speciflcarrangement illustrated. As many modifications of thesystem which are within the scope of the invention will be apparent tothose skilled in the art, I desire to be limited only by the scope ofthe appended I claim as my invention:

1. In a reversible cycle system for heating or cooling a space,in'combination, a refrigeration system having an evaporator, a condenserand a compressor, a heat exchanger in heat exchange relationship withsaid space,' fluid conveying means including valve means for selectivelycom I necting said heat exchanger into fluid circulating relationshipwith said evaporator or saidcondenser, thermostatic means forcontrolling said compressor, changeover means for controlling said valvemeans and also controlling said thermostatic means in a manner to causesaid thermostatic means to start said compressor upon fall intemperature when said heat exchanger is connected to said condenser andto start said compressor upon rise in temperature when said heatexchanger is connected to said evaporator, and outside temperatureresponsive means for controlling said changeover means and for pre-'venting operation of said compressor when out-- side temperature isbetween predetermined values.

2. In a reversible cycle system forheating and cooling 8. space, incombination, a refrigeration system having an evaporator device, acondenser device and a compressor, a heat exchanger in heat exchangerelationship with said space, a

storage tank, fluid conveying meansincluding valve means for selectivelyconnecting said heat exchanger into fluid circulating relationship withsaid evaporator device or said condenser device while maintaining saidstorage tank connected for receiving fluid from one of said devices,thermostatic means for controlling said compressor, changeover means forcontrolling said valve means and also controlling said thermostaticmeans in a manner to cause said thermostatic means to start saidcompressor upon fall in temperature when said heat exchanger isconnected to said condenser device and to start said compressorupon'rise'in temperature when said heat exchanger is connected to saidevaporator device, and means for controlling the temperature in saidstorage tank.

. 3. In a reversible cycle system for heating and cooling, incombination, a refrigeration system having an evaporator device and acondenserdevice, a heat exchanger in heat exchange relationship with amedium to be conditioned. a

ustorage tank for fluid, means for selectively connecting said heatexchanger into fluid circulating relationship with either saidevaporator device or condenser device while maintaining said stor-. agetank connected for receiving fluid from one of said devices, a flowcontroller for controlling the flow. of fluid through said one device,and means responsive to the temperature of the fluid for controllingsaid flow controller.

4. In a reversible cycle system for heating and cooling, in combination,a refrigeration system having an evaporator device and a condenserdevice, a heat exchanger in heat exchange relationship with a medium tobe conditioned, a storage tankfor fluid, means for selectivelyconnecting said heat exchanger into fluid circulating relationship witheither said evaporator device or condenser device while maintaining saidstorage tank connected for receiving fluid from one of said devices,flow control means for controlling the flow of fluid into saidstoragetank, and means responsive to the temperature of the fluid in saidstorage tank for"'controlling said flow control means.

5. 'In a reversible cycle system for heating and cooling, incombination, a refrigeration system having an evaporator device and acondenser device, a heat exchanger in heat exchange relationship with amedium to. be conditioned, a storage tank for fluid, means forselectively connecting said heat exchanger into fluid circulatingrelationship with either said evaporator device or condenser devicewhile maintaining said storage tank connected for receiving fluid fromvone of said devices, a flow controller. for controlling the flow offluid through said one device, means responsive to the temperature ofthe fluid for controlling said flow controller, flow control means forcontrolling the flow of fluid into said storage tank, andmeansresponsive to the quantity of fluid in said storage tank forcontrolling I said flow control means.

6. In a reversible cycle system for heating and cooling, in combination,a refrigeration system having an evaporator device and a condenserdevice, a heat. exchanger in heat exchange relationship with a medium tobe conditioned, a

storage tank for fluid, means for selectively con- I necting said heatexchanger into fluid circulating relationship with either saidevaporator device or said condenser device while maintaining saidstorage tank connected for receiving fluid from one of said devices,temperature respon-' sive means for controlling said refrigerationsystem, temperature responsive means for controlling the temperature insaid storage tank, and timing means for varying the temperaturejmaintained in said storage tank and thereafter preventing operation of saidrefrigeration system.

7. In a reversible cycle system for heating and cooling, in combination,a refrigeration system, means adapted to either heat or cool a space andincluding a storage tank for conditioning medium which is changed intemperature by the refrigeration system, thermostatic means respontiveto the temperature of the stored medium for controlling the temperatureof said medium, timing means for limiting operation of saidrefrigeration system for predetermined periods, and means actuated bysaid timing means forvarying. the temperature of the stored medium priorto said periods.

8. In a reversible cycle system for heating and cooling, in combination,a refrigeration system,

v means adapted to either heat or cool a-space and including a storagetank for conditioning medium which is changed in temperature by therefrigeration system, .a circulating pump for circulating theconditioning medium, temperature responsive means for controlling thecirculating pump, thermostatic means for controlling the perature of thestored medium, timing means for limiting the operation of saidrefrigeration system during predetermined periods while permitting saidcirculating pump to operate, and means actuated by the timing means forvaryin the temperature of the stored medium prior to said periods. I V

9. In a system of the class described, in combination, a refrigerationsystem, means for conditioning a space, said refrigeration systemincluding a compressor, a storage tank for storing conditioning mediumwhich is changed in temperature by said refrigeration system, acirculating pump for circulating conditioning medium between said tankand said conditioning means, temperature responsive means forcontrolling said compressor and circulating Pump, and timing means forlimiting theoperation of said compressor during predetermined periodswhile permitting said circulating pump to continue to operate under thecontrol of said temperature responsive means.

10. In a system for conditioning the air in a space, in combination, arefrigeration system for changing the heat content of the air in saidspace, a storage tank for medium which is changed in temperaturechanging capacity by said refrigeration system, thermostatic means forcontrolling the temperature changing capacityof the medium in saidstorage tank, timing condenser to said heat exchanger and a secondposition causing heat transfer fluid to circulate from said evaporatorto said heat exchanger,

' thermostatic means for controlling the power means for'placing therefrigeration system out of operation during predetermined periods, andmeans controlled by said timing means-for adlusting said thermostaticmeans prior to said periods in such manner that the temperature changingcapacity of said medium is increased.

11. In a system for conditioning a space, in combination, a heatexchanger in heat exchange relationship with said space, a storage tankfor heat exchange medium, piping means for' circulating heat exchangemedium from said storage tank through said heat exchanger, thermostaticmeans for controlling the circulation of heat exchange medium, a powerconsuming means for changing the temperature of the medium in saidstorage tank, thermostatic means responsive to the temperature of saidmedium for controlling said power consuming means for maintaining saidmedium at a predetermined temperature so thatlt has a predetermined heatexchange capacity, timingmeans for placing said powerconsuming means outof operation during predetermined periods, and -means controlled by saidtiming means for adjusting said thermostatic means prior to said periodsin such" a manner as to increase the heat exchange capacity above saidpredetermined capacity. l

12-. In a reversible refrigeration system for heating or cooling aspace, in combination, a conditioning chamber through which air ispassed to said space, a heat exchanger in said chamber, a refrigerationsystem having an evaporator and a condenser, piping means between saidheat exchangerfievaporator, and condenser,

' circulation controlling means, two-position type control means forsaid circulation controlling means, said control means having a firstposition causing heat transfer fluid to circulate from said inputto saidrefrigerationsystem, a low limit thermostat responsive to thetemperature of. the air discharged from said heat exchanger forcontrolling the power input in a manner to prevent the discharge airtemperature from falling below a predetermined value, and changeovermeans for actuating said control means to reverse the system fromheatingto cooling, said changeover also controlling the action of saidthermostatic means and of said low limit thermostat to cause saidthermostatic means to operate on temperature rise and to render said lowlimit thermostat ineffective to prevent the temperature of the dischargeof air from falling below said predetermined value when the controlmeans is operated to place the system on cooling.

13. An apparatus for serially utilizing'a single supply of water forboth heat exchange and a second water using system, said apparatuscomprising aheat exchanger, a line connected to said single supply ofwater for continuously supplying water therefrom to the heat exchanger,a

1 second line from the outlet of said heat exwater supply in excess ofthe requirements of said secondwater using system while maintaining-saidsecond water using system under ade'-'- quate pressure.

14. An apparatus for serially utilizing a single supply of water forboth heat exchange and domestic use, said apparatus comprising a heatexchanger, a line connected to said single supply of water forcontinuously supplying water therefrom to the heat exchanger, a secondline from the outlet of said heat exchanger connecting with a domesticwater supply, a modulating valve in one of said lines for controllingthe flow of water through the heat exchanger, thermostatic means forautomatically controlling said modulating valve in accordance with thetemperature of the water in said apparatus, and valve means operated inresponse to pressure in the apparatus which permits continued fiow ofwater from said single source of 'si pply through said heat exchangerand diverts that portion of the water flowing through the heat exchangerfrom the single water supply which is not needed in said domestic watersupply while maintaining said domestic water supply under adequatepressure.

' ROBERT B. P. CRAWFORD.

